Improvement i n treating vulcanizable gums



UNITED STATES PATENT OFFICE.

CHARLES GOODYEAR, OF NEW HAVEN, CONNECTICUT.

IMPROVEMENT l N T RE ATING VULCANIZABLE GUMS.

Specification forming part of Letters Patent No. 10,738, dated April 4, 1854.

To all whom it may concern Be it known that I, CHARLES GOODYEAR, of New Haven, in the State of Connecticut, have invented certain Improvements in the Manufacture of Caoutchouc, Gutta-Percha, and other Gums and their Compounds; and 1 do hereby declare that the following is a full, clear, and exact description thereof.

Myinvention consists in an improved method of manufacturing caoutchouc and other gums susceptible of vulcanization, and their compounds, in flat or cnrved'sheets or othervdcsired forms or shapes; and it consists in covering the surface or surfaces of the sheets of gum with sheets or plates of paper, cloth, or other material, and then confining the same during the process of vulcanization by press ure between plates of metal or other rigid material, or otherwise.

i I take any of the compounds of caoutchouc or gutta-percha which have been suitably pre-' pared by mixture or contact with sulphur, in order that it may be cured or vulcanized by being subjected to a high degree of artificial heat, according to the process well known to manufacturers of caontchouc. I spread or form the compound into sheets, and I place the sheets ofcom pound between sheetsor plates ofpaper,or ofcotton, or linen, or other cloth, or plates of vulcanized eaoutchouc or gutta percha or other material; and in order of preventing the caoutchouc or its compounds from adhering too strongly to the sheetof paper or other material, I first dust or cover the surfaces of the caoutchouc with finely-pulverized soapstoneorsomeequivalentsubstance. Thesheets of compound thus placed between sheets of paper are placed between plates of iron or other suitable rigid material capable of hear- -ing a high degree of heat without alteration,

whole apparatus of sheets of caoutehouc lying between the sheets of paper or other material and between the plates of iron is then sub.

jected to a high degree of artificial heat-say from260 to 3tl0 'Fahrenheit, or thereabout-- for several-say from three to seven-hours, the heat being gradually raised, using-generally steam h'eatiu a steam-heater, until the process of vulcanization shall be completed. Upon taking the sheets of compound out from between the iron plates it will be found that they have assumed permanently the shape in which they'were heated, so that if the sheets of paper and the plates of iron were smooth and fiat the sheets of compound compressed between them would be smooth and flat. It the sheets of paper or other ma' terial in contact with the sheets of compound were embossed, then the sheets of compound would take impressions from embossed surfaces, and it the plates of iron were curved or irregular in their shapes the sheets of compound would he curved and of similar irregular shapes,'so that by these means sheets or masses of caoutclionc, gutta-percha, or their compound may {be manufactured smooth or embossed, flat or curved, or of other dlesirable form without the ;aid of molds, whichare troublesome and expensive, and in large quantitles at one heating and with one pair of plates.

The sheets of compound may be combined with cotton or other cloths, or with fibrous substances, in order to give strength, or for other purposes, before being placed between the sheets of paper.

Having thus described the nature of my invention and the mode of putting it into operation, what I'claim as my invention, and desire to secure by Letters Patent, is

he method of manufacturing compounds of caoutchouc, gutta-percha, and other gums susceptible of vulcanization in sheets, by covering the surface or surfaces ofthe sheets'of gum with sheets of paper or cloth, or the equivalent thereof, and then confining the same during the processgot' vulcanization by pressure between plates of metal or their equivalents, or otherwise, substantially as described.

CHARLES GOODYEAR. Witnesses:

JOSEPH H. DORR, JAMES A. Dorm. 

